The present disclosure generally relates to switching voltage regulators and, more particularly, to the control circuit for the switching voltage regulator.
Voltage regulators are widely used in electronics devices. For example, a power supply may convert an input voltage to a stable output voltage through the voltage regulator for providing to the load.
Voltage regulators may be roughly categorized into two types, i.e., linear voltage regulators and switching voltage regulators. Although the switching voltage regulators are more complicated, the switching voltage regulators have better energy efficiency and do not require large-sized radiators compared with the linear voltage regulators. Therefore, the switching voltage regulator seems a better choice for utilizing in the portable devices.
There is, however, something to be considered when utilizing the switching voltage regulators. For example, in conventional designs, the amplitude of the ripple of the output current (and therefore the output voltage) of the switching voltage regulator is a function of the input voltage and/or the output voltage of the switching voltage regulator. When the input voltage and/or the output voltage of the switching voltage regulator vary, the amplitude of the ripple of the output voltage varies. Thus, the output voltage of the switching voltage regulator is not stable and results in the malfunction of the load. A good switching voltage regulator should have stable output voltage ripples independent of the input voltage and/or the output voltage of the switching voltage regulator. In other words, the amplitude of the ripple of the output voltage should remain fixed even when the input voltage and/or the output voltage of the switching voltage regulator varies.